This invention relates to a connector for coupling a conduit to a junction box, and more particularly to a set screw connector typically used for coupling intermediate metallic tubing commonly referred to as EMT.
In electrical installations, junction boxes are commonly utilized for an electrical interconnection between separate wires. The wires are carried to the junction boxes by means of conduits or coax cables. Connectors or clamps are commonly utilized to interconnect the conduits to the junction boxes, as is well known in the art.
Each junction box has numerous apertures extending therethrough. Most connectors include a threaded nipple extending from a tubular body portion. The threaded nipple is inserted through one of the apertures in the junction box with the tubular body portion projecting outwardly from the aperture. A lock nut is threaded onto the nipple internally within the junction box so that the lock nut clamps against the inside wall of the junction box, thus securing the connector in place. It is noted, that either a shoulder of the tubular body portion or a second lock nut is engaged against the outside wall of the junction box. The conduit is inserted into the tubular body portion of the connector and secured by means of a set screw radially projecting into the tubular body portion.
Such above mentioned set screw connectors take up a fair amount of space inside the junction box because of the presence of the nipple and the lock nut therein. Especially, when multiple conduits are being fed into a common junction box, the presence of a plurality of such connectors takes up a very large amount of space within the common junction box, thus depriving adequate space therein for making the necessary electrical connections of the wires.
Additionally, since the lock nut is inserted from within the junction box, the electrician often encounters an awkward manipulation to attach the lock nut. Since the lock nut is a separate part of the connector, it may fall down, may get lost, or may cause electrical hazards by falling into electrically sensitive areas whereby it cannot be retrieved.
The lock nut also requires the use of a wrench or socket instrument which must be manipulated from within the junction box. This again provides a potential hazard, since such a tool inside the box may contact electrical wires while the connector is being secured in place.
Accordingly, there is need for an improved connector which can be connected to the junction box from outside the junction box, and which will reduce the amount of space required within the junction box to maintain it in place. Furthermore, a connector is needed that can be connected in a reduced amount of time and effort, and which avoids the possibility of losing parts during its connection in the junction box.